function FullScreen(element){
    if(element.requestFullscreen){
    return element.requestFullscreen();
    }else if(element.webkitRequestFullScreen){
    return element.webkitRequestFullScreen();
    }else if(element.mozRequestFullScreen){
    return element.mozRequestFullScreen();
    }else{
    return element.msRequestFullscreen();
    }
}
function checkboxfull(checkbox,element){
    if(checkbox.checked==true){
    FullScreen(element)
    }else{
    exitFullscreen()
    }
}
function exitFullscreen() {
    if (document.exitFullscreen) {
    document.exitFullscreen()
    } else if (document.msExitFullscreen) {
    document.msExitFullscreen()
    } else if (document.mozCancelFullScreen) {
    document.mozCancelFullScreen()
    } else if (document.webkitExitFullscreen) {
    document.webkitExitFullscreen()
    }
}